The overall objective of this work is to determine how insect hormones may be employed to reduce the abundance and vectorial capacity of mosquitoes. We will define conditions that lead to the rapid degradation of synthetic juvenile hormone larvicides and will compare with the roles of larvae and of micro-organism in the degradation process. These larvicides will be tested in large population cages to measure stability and various effects of these compounds. We will attempt to identify a humoral factor released from the midgut of blood-fed mosquitoes. Perfusion and parabiosis techniques will be employed to determine whether such a factor may induce oogenisis. We will determine whether the replication of arbovirus in mosquitoes is influenced by insect hormones. In an additional study, we will define the differential distribution of peridomestic mosquitoes on Grand Bahama Island. The possibility of competitive displacement between species will be investigated.